Linux KernelOperating system · Linux

CVE-2021-47558

MEDIUM · 5.5 CVSS v3.1 Published 2024-05-24
Fix available
A fix is available. Upgrade to 5.15.6 or later.
See remediation →
57/100
Remediation priority · Elevated
Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
In the Linux kernel, the following vulnerability has been resolved: net: stmmac: Disable Tx queues when reconfiguring the interface The Tx queues were not disabled in situations where the driver needed to stop the interface to apply a new configuration. This could result in a kernel panic when doing any of the 3 following actions: * reconfiguring the number of queues (ethtool -L) * reconfiguring the size of the ring buffers (ethtool -G) * installing/removing an XDP program (ip l set dev ethX xdp) Prevent the panic by making sure netif_tx_disable is called when stopping an interface. Without this patch, the following kernel panic can be observed when doing any of the actions above: Unable to handle kernel paging request at virtual address ffff80001238d040 [....] Call trace: dwmac4_set_addr+0x8/0x10 dev_hard_start_xmit+0xe4/0x1ac sch_direct_xmit+0xe8/0x39c __dev_queue_xmit+0x3ec/0xaf0 dev_queue_xmit+0x14/0x20 [...] [ end trace 0000000000000002 ]---

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis

A detailed technical summary for this CVE is being prepared.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Linux KernelOperating system
Affected:>= 5.10, < 5.15.6= 5.16

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 5.15.6 or later
Fixed in 5.15.6
Vendor patch git.kernel.org →
Recommended fix High confidence

Linux Kernel 5.15.6 or later (5.15.x series), or 5.17 and later

  1. Update your package repository: sudo apt-get update (Debian/Ubuntu) or sudo yum update (RHEL/CentOS)
  2. Install the fixed kernel version: sudo apt-get install linux-image-5.15.6 (Debian/Ubuntu) or sudo yum install kernel-5.15.6 (RHEL/CentOS)
  3. Reboot the system to load the new kernel: sudo reboot
  4. Verify the running kernel version after reboot: uname -r
  5. Confirm the stmmac driver is loaded and functioning: lsmod | grep stmmac
Caveat Kernel upgrades may require rebooting production systems; ensure application compatibility with newer kernel APIs; some older kernel modules may need recompilation

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,600. Get the upgrade done

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-47558 in production — separate from our analysis above.

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What this is

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What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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